Abstract

An energy level of 1.12 eV is found in this paper, which is proposed to dominate the dc degradation process of CaCu3Ti4O12ceramics at high temperature and originated by the migration of oxygen vacancy. In addition, the levels of 0.09 eV and 0.51 eV are suggested to be bulk and domain boundary relaxations, respectively, which show no apparent change after dc electrical degradation. The level of 0.66 eV is proposed to be grain boundaryrelaxation, which cannot be observed after degradation. The increment of permittivity after dc electrical degradation is resulted from the charges accumulation near the electrodes.